Chemically treated substrate strips in screens for open hole gravel packing and stand alone screens

ABSTRACT

A production string and method of preventing accumulation of a compositional material in a production string. An inhibitor strip is disposed in a fluid inflow device of the production string. Fluid is received at the inhibitor strip in the fluid inflow device from a formation. The inhibitor strip includes a chemical inhibitor that interacts with a chemical in the fluid to reduce the production of the compositional material in the production string.

BACKGROUND

In the resource recovery industry, a production system is used in a wellbore in order to draw fluid from a formation surrounding the wellbore and deliver that fluid to a surface location. The fluid from the formation generally includes various chemicals that will deposit on any of the tubulars, screens, pumps, and any other components it comes into contact with as it travels to the surface, thereby forming compositional material such as scale, paraffin, and asphaltenes on these components. Such build-up of compositional material can create a significant restriction in the production string, eventually inhibiting the flow of fluid from the formation. Therefore, there is a desire to be able to prevent build-up in a production system.

SUMMARY

In one aspect, a method of preventing production of a compositional material in a production string is disclosed. The method includes disposing an inhibitor strip in a fluid inflow device of the production string and receiving a fluid at the fluid inflow device from a formation at the inhibitor strip, wherein a chemical inhibitor of the inhibitor strip interacts with a chemical in the fluid to reduce the production of the compositional material in the production string.

In another aspect, a production string is disclosed. The production string includes a fluid inflow device and an inhibitor strip disposed in contact with the fluid inflow device, the inhibitor strip including a chemical inhibitor therein to interact with chemicals in a fluid flowing through the fluid inflow device to reduce the production of a compositional material in the production string.

BRIEF DESCRIPTION OF THE DRAWINGS

The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:

FIG. 1 shows an illustrative production system;

FIG. 2A shows a section of the production string having a fluid inflow device capable of reducing or preventing the scale production within the production string;

FIG. 2B shows a detailed view of the first fluid inflow device of FIG. 2A;

FIG. 3 shows an illustrative inhibitor strip for disposal between the base pipe and wire screen of FIG. 2B;

FIGS. 4A and 4B shows cross sections of an inhibitor strip in different embodiments;

FIG. 5 shows a perspective view of a partially constructed fluid inflow device;

FIG. 6 shows a perspective view of a subsequent construction stage of the fluid inflow device; and

FIG. 7 shows a perspective view of the fluid inflow device in another embodiment.

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

Referring to FIG. 1, an illustrative production system 100 is shown. The production system 100 includes a production string 102 extending from wellhead 104 located at a surface location 106 into a wellbore 108 formed in a formation 110. The production string 102 includes a plurality of tubular members attached end to end, such as tubular members 102 a, 102 b, and 102 c. The production string 102 extends through the formation 110 to reach a reservoir 112 in the formation. The production string 102 further includes at least one section having a fluid inflow device 114. While only a single fluid inflow device 114 is shown for illustrative purposes, in various embodiments, a plurality of fluid inflow devices and related components can be deployed along the production string 102. In various embodiments, production string 102 is disposed in the wellbore 108 so as to place the fluid inflow device 114 within the reservoir 112. Packers 120 and 122 can be deployed from the production string 102 in order to isolate an annular section 124 of the wellbore 108 between the fluid inflow device 114 and the reservoir 112 to allow the flow of fluid from the reservoir 112 into the fluid inflow device 114. A pump 128 can be used to pump or direct fluid from the reservoir 112 to the surface location 106. During production, the fluid 125 is pumped from the reservoir 112 into the production string 102 via the fluid inflow device 114, up through the tubular member 102 a, 102 b, 102 c to reach the wellhead 104 at the surface location 106 through the production string 102. A standpipe 132 at the surface location is used to direct the fluid from the wellhead 104 to a storage facility 130.

The fluid 125 includes therein various chemicals which are responsible for a growth of scale on various surfaces of the production system that come into contact with the fluid 125. These chemicals precipitate from the fluid 125 due to changes in pressure and temperature as the fluid flows through the production system and settles on the various surfaces and/or components. This precipitated material, or compositional material, refers to scale, paraffin, and/or asphaltene and can result in reduced flow channels in the production string, destruction of the pump 128, as well as difficulties in downstream refining.

FIG. 2A shows a section 200 of the production string 102 having a fluid inflow device capable of reducing or preventing the production of compositional material within the production string 102. The section 200 includes a first fluid inflow device 202 and a second fluid inflow device 204. A first connector 206 couples the first fluid inflow device 202 to the second fluid inflow device 204. A second connector 208 can also be used to connect the first fluid inflow device 202 to other components of the production string 102, including other fluid inflow devices.

FIG. 2B shows a detailed view of the first fluid inflow device 202 of FIG. 2A. The first fluid inflow device 202 includes a base pipe 210 having perforations 212 therein to allow fluid from the formation to flow into an interior 214 of the base pipe 210 and uphole through the production string 102. The base pipe 210 is surrounded by at least one wire screen 216 circumferentially surrounding the base pipe 210 and separated from the base pipe by an annular region 215. The wire screen 216 has holes or apertures that are sized to selectively allow fluid into the first fluid inflow device 202 while keeping out particles greater than the size of the holes. The annular region 215 between the base pipe 210 and the wire screen 216 includes one or more scale inhibitor strips 218 disposed therein. Details of the inhibitors strips 218 are shown in FIGS. 3, 4A and 4B.

FIG. 3 shows an illustrative inhibitor strip 218 for disposal between the base pipe 210 and wire screen 216 of FIG. 2B. The inhibitor strip 218 is in the shape of a rectangular cuboid having a length l, width w and thickness t. The thickness of the inhibitor strip 218 is selected to allow the inhibitor strip 218 to fit within the annular region 215 between the wire screen 216 and the base pipe 210. The width of the inhibitor strip 218 can be selected to fit along the curved surface of the base pipe to suitable approximation.

FIGS. 4A and 4B shows cross sections of an inhibitor strip 218 in different embodiments. FIG. 4A shows a cross-section 400 of a coated inhibitor strip 218. The cross-section 400 shows a base material 402 having a coating of a chemical inhibitor 404 surrounding its surface. FIG. 4B shows a cross-section 401 in which the inhibitor strip 218 includes a base material 402 that is impregnated with the chemical inhibitor 404. As fluid flows across the inhibitor strip, the chemical inhibitor 404 reacts with chemicals in the fluid responsible for compositional material production, thereby preventing or reducing scale, paraffin, and/or asphaltene productions. The inhibitor can be a chemical that interacts with chemicals in the formation fluid that otherwise result in scale, paraffin, and/or asphaltene production.

Over time, the chemical inhibitor in or on the inhibitor strips becomes depleted due to the interactions with the chemicals in the fluid. At a selected time, the inhibitor strips can be recharged by flowing a fluid chemical inhibitor into the wellbore and into contact with the inhibitor strips.

FIG. 5 shows a perspective view 500 of a partially constructed fluid inflow device. The perspective view 500 includes the base pipe 210 and a first cylindrical arrangement 502 of inhibitor strips 218 arranged around a circumference of the base pipe. The lengths of the inhibitor strips 218 extend or are elongated along a longitudinal axis of the base pipe 210. The first cylindrical arrangement 502 covers a first axial section 504 of the base pipe. A second axial section 506 of the base pipe is shown uncovered.

FIG. 6 shows a perspective view 600 of a subsequent construction stage of the fluid inflow device. A second cylindrical arrangement 602 of inhibitor strips 218 are shown around the second axial section 506 of the base pipe 210. The wire screen 610 is shown over a section of the first cylindrical arrangement 502. During construction the wire screen 610 can slide along the longitudinal axis of the base pipe 210 to encapsulate each cylindrical arrangement once completed.

FIG. 7 shows a perspective view 700 of the fluid inflow device in another embodiment. A plurality of dividers 702 are formed between the base pipe 710 and the wire screen 716 to form a plurality of drainage channels 704. Inhibitor strips 218 are disposed within the drainage channels, thereby causing the fluid to flow across the inhibitors strips 218 as it flows from the wire screen 716 to the base pipe 710 via the drainage channels.

Set forth below are some embodiments of the foregoing disclosure:

Embodiment 1. A method of preventing production of a compositional material in a production string. The method includes disposing an inhibitor strip in a fluid inflow device of the production string; and receiving a fluid at the fluid inflow device from a formation at the inhibitor strip, wherein a chemical inhibitor of the inhibitor strip interacts with a chemical in the fluid to reduce the production of the compositional material in the production string.

Embodiment 2. The method of any prior embodiment, wherein the fluid inflow device includes a base pipe and a screen forming an annular region around the base pipe, further comprising disposing the inhibitor strip in a channel between the base pipe and the screen.

Embodiment 3. The method of any prior embodiment, wherein the screen and the base pipe form one or more drainage channels, further comprising disposing the inhibitor strip in the one or more drainage channels.

Embodiment 4. The method of any prior embodiment, wherein the inhibitor strip is elongated along a longitudinal axis of the base pipe.

Embodiment 5. The method of any prior embodiment, wherein disposing the inhibitor strip further comprising placing a plurality of inhibitor strips circumferentially around an axial section of the base pipe.

Embodiment 6. The method of any prior embodiment, wherein the inhibitor strip includes a base material that is one of: (i) coated with the chemical inhibitor; and (ii) impregnated with the chemical inhibitor.

Embodiment 7. The method of any prior embodiment, further comprising recharging the inhibitor strip with the chemical inhibitor at its location in the wellbore.

Embodiment 8. The method of any prior embodiment, wherein the compositional material includes at least one of scale, paraffin and asphaltene.

Embodiment 9. A production string. The production string includes a fluid inflow device and an inhibitor strip disposed in contact with the fluid inflow device, the inhibitor strip including a chemical inhibitor therein to interact with chemicals in a fluid flowing through the fluid inflow device to reduce the production of a compositional material in the production string.

Embodiment 10. The production string of any prior embodiment, further comprising a base pipe of the fluid inflow device, and a screen forming an annular region around the base pipe; wherein the inhibitor strip is disposed within the annular region.

Embodiment 11. The production string of any prior embodiment, further comprising one or more drainage channels between the base pipe and the screen, wherein the inhibitor strip is disposed within the one or more drainage channels.

Embodiment 12. The production string of any prior embodiment, wherein the inhibitor strip is elongated along a longitudinal axis of the base pipe.

Embodiment 13. The production string of any prior embodiment, wherein the inhibitor strip further comprises a plurality of inhibitor strips disposed circumferentially around an axial section of the base pipe.

Embodiment 14. The production string of any prior embodiment, wherein the inhibitor strip includes a base material that is one of: (i) coated with the chemical inhibitor; and (ii) impregnated with the chemical inhibitor.

Embodiment 15. The production string of any prior embodiment, wherein the inhibitor strip is capable of being recharged with additional chemical inhibitor when deployed in a wellbore.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity).

The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a wellbore, and/or equipment in the wellbore, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.

While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. 

What is claimed is:
 1. A method of preventing production of a compositional material in a production string, comprising: disposing an inhibitor strip in a fluid inflow device of the production string, the inhibitor strip having a coating of a chemical inhibitor on a surface of the inhibitor strip; and receiving a fluid at the fluid inflow device from a formation to flow across the inhibitor strip, wherein lithe chemical inhibitor interacts with a chemical in the fluid to reduce the production of the compositional material in the production string.
 2. The method of claim 1, wherein the fluid inflow device includes a base pipe and a screen forming an annular region around the base pipe, further comprising disposing the inhibitor strip in a channel between the base pipe and the screen.
 3. The method of claim 2, wherein the screen and the base pipe form one or more drainage channels, further comprising disposing the inhibitor strip in the one or more drainage channels.
 4. The method of claim 2, wherein the inhibitor strip is elongated along a longitudinal axis of the base pipe.
 5. The method of claim 2, wherein disposing the inhibitor strip further comprising placing a plurality of inhibitor strips circumferentially around an axial section of the base pipe.
 6. The method of claim 1, wherein the inhibitor strip is further impregnated with the chemical inhibitor.
 7. The method of claim 1, further comprising recharging the inhibitor strip with the chemical inhibitor at its location in the wellbore.
 8. The method of claim 1, wherein the compositional material includes at least one of scale, paraffin and asphaltene.
 9. A production string, comprising: a fluid inflow device; and an inhibitor strip disposed in contact with the fluid inflow device, the inhibitor strip having a coating of a chemical inhibitor on a surface of the inhibitor strip that interacts with chemicals in a fluid flowing through the fluid inflow device and across the inhibitor strip to reduce the production of a compositional material in the production string.
 10. The production string of claim 9, further comprising: a base pipe of the fluid inflow device; and a screen forming an annular region around the base pipe; wherein the inhibitor strip is disposed within the annular region.
 11. The production string of claim 10, further comprising one or more drainage channels between the base pipe and the screen, wherein the inhibitor strip is disposed within the one or more drainage channels.
 12. The production string of claim 10, wherein the inhibitor strip is elongated along a longitudinal axis of the base pipe.
 13. The production string of claim 10, wherein the inhibitor strip further comprises a plurality of inhibitor strips disposed circumferentially around an axial section of the base pipe.
 14. The production string of claim 9, wherein the inhibitor strip is further impregnated with the chemical inhibitor.
 15. The production string of claim 9, wherein the inhibitor strip is capable of being recharged with additional chemical inhibitor when deployed in a wellbore. 